1. Derive an expression for the location of cm, the center of mass of a system that consists of a long thin rod with two masses clamped to the rod. Assume that the rod has length I and mass m and that the centers of the clamped masses m and m2 are located at positions and 2. Let the origin of the coordinates be the end of the rod closest to the mass m (labeled "top" in figure 9.3). 2. Prepare a spreadsheet where you can enter the values of m, m2 and m in one column and x1, x2 and 1 in an adjacent column as shown here Mass m1 m2 m m (g) x (cm) 197.0 27.65 353.3 88.3 381.2 121.6 Add appropriate calculations to your spreadsheet that will allow you to calculate the value of xcm from the 6 entry numbers in this table. You should code your spreadsheet so that you can simply replace these 6 numbers with the numbers you measure in lab and have the new results correctly calculated. If your answer to part 1 is correct and your spreadsheet is correctly coded you should find that for the preceding data, cm 64.2 cm. XI Top m1 m2 O x2